Polyesters such as poly(3-hydroxybutyrate) (PHB) have attracted commercial and academic interest as new biotechnological materials. In previous studies it was confirmed that two commercial lipases hydrolyzed the ester bonds from the 3HB fractions of P(3HB-co-4HB) copolymer. In this study, one of the previously used commercial lipases has been used for the enzymatic degradation of PHB homopolymer obtained via fermentation with Cupriavidus necator in order to obtain low molecular mass polymer. The results confirmed the enzymatic reaction of the used lipase with this PHB and show a controlled decrease of the molecular mass from 300,000 Da–4000 Da.